Conventional manufacturing methods for yaw rate sensors and acceleration sensors are available. In one widely used method, a plurality of freestanding functional structures made of polycrystalline semiconductor material, for example, is provided on a substrate. Partially buried printed conductors and electrodes are situated beneath these functional layers, as is described in German Patent Application No. DE 195 37 814 A1. The micromechanical structures produced in this way are often sealed with a cap wafer or a cap substrate in the further process sequence for manufacturing micromechanical devices. Depending on the application, a suitable pressure is enclosed within the closed volume produced by closing the housing. In yaw rate sensors, a comparatively low pressure, i.e., a gas composition having a comparatively low pressure, is normally enclosed, typically at a pressure of 1 mbar (i.e., 1 hPa). The basis is that in these sensors a portion of the movable structure is resonantly driven. At a fairly low pressure, such an excitation motion may be generated with relatively low voltages due to the low damping. In contrast, in acceleration sensors it is not desirable for the micromechanical structure of the sensor to be set in vibration, which would be possible if an external acceleration were applied. Therefore, these sensors are normally operated at higher internal pressures of the closed volume, i.e., the cavern, typically at 500 mbar (500 hPa).
For the combined manufacture of yaw rate sensors and acceleration sensors, it is possible to implement a yaw rate sensor as well as an acceleration sensor on a substrate, and via a shared cap wafer which for each functional unit of such a combined sensor system, i.e., for each chip, provides two caverns or cavities that are closed by the substrate and the cap substrate. The sensors are thus encapsulated on the substrate level. However, conventionally, it is comparatively complicated and expensive in such a case to implement different pressures in the cavity of the yaw rate sensor and in the cavity of the acceleration sensor, since this normally requires a comparatively large surface area usage for producing a getter layer, and an increased level of effort for sealing same during manufacture, prior to closing the sensor housing.